A Thailand study by the CDC and UNAIDS revealed that a shorter-than-usual course of AZT—in the last four weeks of pregnancy and during labor—cut the risk of mom-to-infant HIV transmission by 50 percent. The results, though not as dramatic as the 70 percent reduction with the longer, more costly course reported by a 1994 U.S. study, offer a feasible alternative for developing countries—where 90 percent of HIV infections occur. The shorter version costs about $80 per woman; the prolonged course about $800.

Due to the trial’s success, officials from the CDC, UNAIDS and the National Institutes of Health recommended that placebo use—a controversial practice slammed by many as unethical—be halted in all six mother-to-child transmission studies worldwide. “This confirms what we’ve been saying for a year—that some short regimen would be better than nothing,” said Dr. Peter Lurie, research associate at Public Citizen's Health Research Group. “If the CDC had paid heed, we wouldn’t have dozens of infected infants.”  

After an activist uproar, Glaxo Wellcome slashed the cost of AZT for pregnant women with HIV in developing countries—the first time a large drug company has discounted the price of an AIDS med to get it to hard-hit regions. The company also announced it will consider chopping the price of 3TC if that med proves similarly effective.